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At the start of last month we headed over to the Superbooth 16 event in Berlin, put together by the lovely people from Schneidersladen in Berlin, Germany.

​All the pre-event information around the event seemed to suggest something a little different from a normal trade show, with an eclectic mix of performance, conversation, culture, product demos and workshops open to everyone.

Even halfway into the first day of the event it became evident that there was a really nice vibe in the Funkhaus, and everyone that stopped to chat to us at our booth was super informed and genuinely interested. Our booth was located next to fellow DIYers Befaco and Thonk, we were also very lucky to meet Jan from Ginko Synthese and Martin from Rebel Technology who were also beside us, which all in made for lots of nice conversations during the quiet spots in the day, and checking out some great modules too of course including Befaco's Rampage and Sampling Modulator modules, Ginko's awesome real time Sample Slicer and Grains (nice Arduino based programmable) modules, and some very neat new Rebel Technology prototypes including an implementation of control voltage over WIFI! and oscilloscope modules. ​

Our DIY workshop on the Friday afternoon rolled around pretty quickly and we had a full house, luckily the sun was out so we had lots of light in the room and after a short few hours focusing on the soldering at hand a we had 5 x LVLS modules, 2 x LFOs and 3 x Bazz Fuss pedals put together and out into the wild, along with a few curious and slightly bewildered onlookers who popped their heads in during the workshop for a look, and a couple of people who signed up for the Befaco DIY workshop the next day.

With such a packed programme of events over the 3 days it was pretty difficult to see everything that was scheduled, a couple of other main highlights that we caught included the spectacular Bernhard Rasinger AV performance and Erica Synths demo of their new Pico range of modules (wow!), but, to be honest what made the event for us really was the conversations that we had mostly at our booth, and it's true in this sense that dedication more than makes up for numbers.

I think it was mentioned elsewhere about the conversations during the weekend that many people were genuinely interested in the technical and musical aspects of all the gear that was being demo'ed, rather than being given a pitch by someone from the sales and marketing department, and this was definitely the feeling most evident when chatting among the booths with other module makers or taking a break outside beside the river.

Of course it's pretty impossible to try and capture in words what it was about Superbooth that was so unique, suffice to say that the careful planning in creating exactly the right atmosphere for attentive listening throughout was very much appreciated. On that note, Ask Audio have a short interview with Superbooth CEO Andreas Schneider here with some more on this..

A quick post on how to get the most out of our Patchblocks for Eurorack module and get it communicating with other Eurorack modules, by looking at how the module hardware interacts with the Patchblocks software environment.

We're going to look at how to send inputsignals into the DSP environment and change the DC offset of the signal, how to send triggers and gates signals to and from the module, syncing Patchblocks oscillators with other oscillators in a modular system, and how to use control voltages to change parameters in a patch or to use the CV inputs as additional audio inputs. ​

INPUT SIGNALS

The module hardware scales incoming bi-polar voltages of +10v/-10v to a range that is read by the Audio Input block (see pic above), the signals are then mapped to the range of 0.5 to -0.5 in the Patchblocks editor.

So, a bi-polar input voltage of 20 volts peak to peak will be in the range -0.5 to 0.5 in the Patchblocks editor, a unipolar voltage of 0 to +10v peak to peak will be in the range 0 to 0.5 in the Patchblocks editor.

There is a slight DC Offset on the hardware, to compensate for this we can use the Add block in the software to subtract a value of -0.05. This will set the zero crossing point of the incoming bi-polar signal to 0 in the Patchblocks editor.

The left input on the module (IN) corresponds to the Left analogue channel in the Audio Input block, the right input the Right analogue channel. As of software update 0.5.3 the Audio Input block adds code to invert the incoming signal. This corrects the inversion on the module hardware, so incoming signals will be in phase with signals generated in the editor. ​

GATE/TRIGGER INPUTS

The GATE inputs on the module are inputs for the 2 buttons in the Patchblocks editor, which are accessible using the Controls block. Pressing the button will activate the function the control is assigned to in the patch. Instead of pressing the button, an incoming voltage of amplitude +5v will also activate a button press.

In this patch above, the two buttons are assigned to trigger two small samples, deux and un. The samples can also be triggered by a short pulse of +5v sent to the GATE input.

We've tested the speed/response of the GATE inputs with incoming triggers of speeds down to 50 micro seconds. If you're having trouble with triggering samples or drums, make sure the Amplitude of the Input signal is high enough - it's expecting a +5v signal.

The GATE inputs are not velocity sensitive; the input is read as a value of either 0 or 1 in the Patchblocks editor. However they are time sensitive, so a +5v pulse of a longer duration can be used to trigger the length of an envelope in the editor. ​

Sending trigger or gate signals from the module

The triggers in the Patchblocks editor are normally short negative polarity pulses. To convert these to positive polarity triggers of +5v, we need to perform a couple of functions in the editor.

This patch above takes triggers from the GATE inputs (which could also be triggers generated anywhere in the Patchblocks Editor for example from the Impulse block), converts them to random triggers and division of 3 triggers, and routes them to the two Audio Outputs. If we look at the two blocks before the Audio Output, the Gate block in the editor can be used to set the length or duration of the output trigger, and the Multiply block contains a value of -1, which inverts the trigger signal from a negative polarity pulse to a positive polarity pulse. ​

SYNCING Patchblocks oscillators with other oscillator modules

The GATE inputs can also be used to sync Patchblocks oscillators with other oscillators in a Eurorack system.

Patchblocks oscillators have a Reset input, which if a non-zero value is received (say a value of 1), will hold it's output at the peak of the wave until the duration of the reset signal is complete (back to 0). A trigger signal of +5v amplitude at the GATE inputs can be used as a reset signal for the oscillators in the Patchblocks Editor.

The control voltage inputs

Similar to the GATE inputs, the CV inputs are control voltage inputs for the 2 assignable knobs in the Patchblocks editor, accessed using the Controls block.

On the hardware these inputs are expecting a bi-polar input signal of -5v to +5v, although signals of higher amplitudes can also be sent. This signal is then mapped to a range of 0 to 1 in the Patchblocks editor.

The CV inputs can also be used as audio inputs by using the Add block in the editor and adding a value of -0.5 - this will bring the range of the input signal into the same range in the editor as the Audio Input block (-0.5 to 0.5).

When an input signal is present, the control knob acts as an attenuator - roll it all the way to the left to allow the full CV signal through or increase clockwise to attenuate the amount of the CV signal affecting the patch parameter. If you have a version 0.9 PCB (check the silkscreen on the printed circuit board on the back of the module) then the CV inputs are inverted, if you have a version 1.0 PCB the CV inputs are not inverted.

That's it for now! Hopefully the above tips will help to get the most out of using the Patchblocks module with other modular and non-modular gear, if you have any comments or questions please let us know in the comments or shout us email at info (at) maker.ie. Happy patching!

Following on from last week's post on power supplies, we thought it might be helpful to do a short post on how to measure how much current a guitar pedal or synth module is drawing under normal operating conditions.

We'll only need a couple of tools for this - pedal/module and power supply, a Multimeter, and a couple of crocodile clips.

Connecting the MultimeterWe're going to use the Multimeter to measure the current draw (in Amps). To measure current, we have to insert the Multimeter in series with the device we want to measure:

Guitar Pedal (Single Power Supply)For a pedal or circuit which is normally powered from a single power supply or battery, we want to insert our Multimeter between the positive (9V) supply and the power connection of the circuit (PCB).

​The power supply ground (GND) or negative of the battery should connect to circuit ground (PCB). Set the Multimeter to the mA range, and the current measurement should display on the meter:

This sine wave oscillator PCB is drawing 12.05mA from the battery. Make sure the tips of the crocodile clips are not touching each other at the battery or power adaptor pins or at the circuit PCB, otherwise the positive voltage will be shorted to ground (GND).

​Synth Module (Dual Power Supply)For a synth module which is typically powered from a dual power supply (+12/15V and -12/15V), we will want to measure the current on both the +12V and -12V lines. To do this, measure the current on either the +ve or -ve rail while the other voltage rail and GND connections are in place, then repeat for the other rail.

Again, make sure the tips of the crocodile cables don't touch each other, or any of the 3 middle pins of the connector (GND), as this will cause a short circuit to ground. This is a little trickier with the standard Eurorack 10pin power headers due to the small pitch between the connectors, so take it slowly. One tip is to use 3x SIL pins and insert into the cable header coming from the power supply, to allow a bit more space between the crocodile clips:

Or another alternative could be to solder a small piece of wire or component leg to the connector to extend the connection length if needed.

This LFO module below is drawing 15.52mA on the +12v power line:

For synth modules, its probably better to use a separate small power supply (something like this for example) for measuring current and other testing and DIY modding/hacking.... we wouldn't recommend doing this with any other modules mounted in your case or powered at the same time.

That's it! You can also use this method to measure the current draw of any electronic device (not just pedals and synths). What are we actually measuring when we measure current? The numbers on the Multimeter are the rate at which electric charge passes a point in a conductor over time.

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